I just want to make one caveat to what you're saying. The bank doesn't own the house in a mortgage. What the bank owns is the debt in the mortgage with a claim to the house if owner fails to pay the debt. The bank would have to go through the foreclosure process before they can take ownership of the house.I can't believe I have to chime in on this again but Guyin Cognito is correct:
The bank owns the house, Ophelia is responsible for the mortgage payments and Hunter is the one paying each payment in full. When Hunter is introduced Ophelia says "He's staying with us to help with the mortgage.". Then, as pointed out by Macinnes, Hunter says to Sterling when they're alone "I’m not helping with the house payments. I’m paying the entire thing.". He's paying the entirety of each mortgage payment.